1. Field of the Invention
The field of the invention is that of the so-called “head-up” display systems comprising a removable sun visor. These systems are called “head-up displays” or “HUD”. These systems are mainly used in aeronautics.
A so-called “head-up” display system essentially comprises a display, an optical system and an optical element called optical combiner or optical mixer. The optical combiner is generally a semi-reflecting planar or curved glass plate. The assembly makes it possible to give the user a collimated image superimposed on the outside landscape. In the case of aeronautical applications, when the display system is mounted inside an aircraft cockpit, this image may include a variety of information on the piloting or the navigation of the aircraft.
2. Description of the Prior Art
In certain sunlight conditions, it is necessary to reduce the brightness of the outside landscape so as to retain sufficient contrast in the image displayed, the brightness of the image necessarily being limited by the performance levels of the displays. The simplest way to proceed is to add a removable “sun visor” en the face of the combiner situated between the combiner and the sun visor of the appliance. The “sun visor” is a curved thin plate, transparent and tinted.